Filters



H. F. BRIED Feb. 1o, 1959 FILTERS 4 Sheets-Sheet 2 Filed Sept. 6, 1955Attorney H. F. BRlED Feb. 10, 1959 FILTERS 58 AWA ffm.

Feb. 10, 1959 H. F. BRU-:D 2,873,028

' FILTERS Filed Sept. 6. 1955 4 Sheets-Sheet 4 United States PatentFrLTERs Henry Francis Bried, Wilmington, Del. Application september 6,195s, serial N. 532,525

' s claims. (C1. 21o-40p` This invention relates to filters of theendless grid'carrying type.

An object of the invention is to provide a filter comprising a series fgrids and an endless valve member wherein means are provided foraligning passages in the grids and valve member, such aligning meansforming a connection between each grid and the valve'mer'nber forsimultaneous travel thereof. p

Another object is to provide a filter 'of the type set forth whichincludes means for insuring constant alignment of the filter medium inorder to prevent lateral Wandering with respect to the grids. Thislateral wandering has heretofore presented, a great problem in respectof machines wherein the filter medium is not attached'dir'ectly to themachine but operates freely therein.

Another object is to provide means for conveniently mounting theoperating portion in the filter machine whereby it may be easily andrapidly removed therefrom to permit ready replacement of the Valve andassociated elements. In machines heretofore proposed, this step may takeas long as seven to ten days, whereas, the present invention makes itpossible to perform this step in a matter of a few hours.

Other objects, details and advantages will become apparent from thefollowing description and accompanying drawings, in which Figure l is asideelevation, partly in section, of a filtering machine in accordancewith the invention,

Figure 2 is an end elevation, partly in section, of such filteringmachine,

Figure 3 is a plan view of the filtering machine,

Figure 4 is an enlarged plan view of a portion of an endless gridcarrier belt,

Figure 5 is an enlarged sectional transverse view of the grid carrierbelt and associated elements,

Figures 6 to 10 are enlarged sectional transverse views of modifiedforms of grid carrier belts,

Figure ll is a side elevation of a modified form of filtering machine,and

Figures l2 to 17 areenlarged sectional transverse views of various formsof grid carrying chains such as may be employed in the machine shown inFigure ll.

Referring to Figures l to 5, inclusive, 1 is a supporting frame in whichare rotatably mounted a pair of horizontally disposed supporting drums2. Mounted on the drum Z is an endless carrier belt 3 of approximatelythe width of the drums composed of an inherently flexible material suchas rubber, rubber fabric, fabric or the like. The carrier belt 3 isprovided with marginal side walls 4 extending perpendicularly from thebody portion of the carrier belt. Each side wall is of minor height topermit passage of the carrier belt over the drums 2 without unduedistortion of the carrier belt. The height of the side walls isdependent on the diameter of the end drums and resulting distortion.This distortion can -be relieved by partially'slitting the walls atintervals. The walls 4 may be formed integrally with the carrier belt 3or they may be separately formed and rigidly xed to the strip.

Fixed to the outer `surface of carrier belt 3 between side walls 4, asby means of rivets or screws 5, are a series of rigid grids 6 formed ofstainless steel or other metal, plastic composition, or the like. Eachgrid 6 is relatively narrow, depending on the diameter of the end drums2, to permit easy passage over the ends. In the horizontal position oftravel of the carrier belt and grids, the side edges of the grids are inclose proximity with each other. Each grid 6 has a centrally arrangedopening or passage 7 registering with a corresponding opening or passageS in thecarrier belt 3. The face of the grid 6 is provided with aplurality of raised portions 9 for engagement by and support of anendless filter medium 10. The grid 6 may also have marginal ribs 11 andintermediate ribs 12 extending across the central opening 7 to providesuitable support for the filter medium thereon. The bottom wall of eachgrid is preferably inclined towards its opening 7 and arranged toprovide channels for directing liquid into the opening.

A valve member comprising a relatively narrow endless belt 13 engagesthe midportion of the under surface of carrier belt 3. Valve member 13is preferably formed of rubber, rubber fabric or the like. Valve member13 is provided with a series of openings or passages 14 each in registrywith an opening 8 of carrier belt 3 and opening 7 of a grid. As shown,each-drum 2 is circumferentially grooved at 15 to permit passage of thevalve member 13.

A suction or vacuum box 16 is mounted on supporting beams 17 carried byframe 1. As shown in Figure 1, beams 11 are fixed to the frame by bolts18 and box 16 is fixed to the beams by bolts 19. Thus, the box may beeasily mounted in or removed from the frame 1. Conduits 20, connected toa suitable source of vacuum, are connected to the bottom portion of box16. As shown, box 16 is elongated in shape and extends throughoutsubstantially the entire upper portion of horizontal travelling movementof the carrier belt 3 and valve member 13. The box illustrated has threelongitudinally aligned compartments 21, each of which communicates witha couduit 20. The box may be formed in one piece or may comprise severalseparate aligned compartments 2l.. The top wall of the box is inengagement with the valve member 13. Such top wall has one or morelongitudinally aligned slots 22 communicating with the interior of thebox and arranged for successive registry with passages S and 7.

.The filter medium 10 comprises a belt of foraminous or porous materialsuch as plastic, cotton or wire cloth or the like. As shown, the filtermedium 10 extends over and in engagement with the upper travellingportion of grids 6 and is supported in its return or lower travellingportion by rollers 24 carried by the frame. A pivotally mounted belttightening roller 25 is preferably included to maintain the filtermedium in any required taut condition.

A feed box 26 is provided at the feed end of the machine and may be inU-shaped form with slightly flaring side walls 27 positioned closelyadjacent but slightly above the filter medium. A feed spout-28 isarranged to feed fluid material containing solids into the box. It willbe apparent that the side walls 27 will retain the material on thefilter medium and prevent it from spilling over` Patented Feb. 1o, 1959the we t material will be in non-fiowable or caked condition and willremain upon the filter medium.

A receptacle 29 is provided at the discharge end .of

ing to the filter medium and direct it into receptacle 29.

A pair of rollers 33 may be provided to supportvthe medium for passageacross the jet 32.

Means for cleaning the filter medium may comprise a pair of spray jets34, a pan 35 being provided to collect the spraying liquid.

The carrier belt 3 and valve member 13 may be supported during theirreturn or lower portion of travel by means such as a plurality ofrollers 36 mounted in the frame and engaging the carrier belt 3 or thegrids 6. A spray jet 37 may be provided to effect a cleaning action onthe grids 6.

A very important feature of the invention resides in the provision of ashort piece of tube 38 which extends rthrough each passage 8 in carrierbelt 3 into the registering passage 14 in valve member 13. Tube 38 maybe of any suitable cross section, such as round, square, oblong orrectangular, depending upon the cross-sectional shape of the pasages.Tube 38 is fixedly mounted in such relation and constitutes a positivealigning means for such passages as well as a connection between thegrids 6 and valve member 13 for simultaneous travel thereof. It will beapparent that it is highly important that the passages 8 and 14 be inpositive registry at all times and thus that the grids 6, carrier belt 3and member 13 travel together as Va unit. Since the valve member is thusfirmly attached to the grids by means of the tubes 38, the frictionalresistance of the valve member in travelling over the vacuum box isovercome.

The entire core of the machine, including the end drums, is supported inthe frame on cross beams 66. The beams 66 may be mounted in the frame bybolts 67. Thus, by removal of such bolts, which may be only four innumber, the entire core may be withdrawn from the frame for thereplacement of parts, such as the valve member.

Figure 6 illustrates a modified form of filter assembly wherein thecarrier belt 3 is provided with flexible grids 39 and a metal plate 40is interposed between the valve member 13 and carrier belt 3, the tubes38 being fixed to plates 40 to ensure more rigid mounting thereof. Asshown the marginal portions of carrier belt 3 and the grids 39 thereonare bendable upwardly, as by means of a slide 41 or similar means,carried by the frame, to impart a troughlike shape to the carrier beltand in this case, flexible grids during their upper horizontaltravelling movement and thus provide a retaining means during itsfiowable state of the material thereon.

Figure 7 shows a further modified arrangement wherein metal or likerigid grids 42 on carrier belt 3 terminate inwardly of the marginalportions of carrier belt 3 to permit upwardly flexing movement thereofby the slides 41 in order to achieve a troughlike shape.

Figure 8 shows an arrangement wherein side bars 43 carried by the framehave their lower edges in close proximity to the filter medium 10 andadjacent the side edges thereof to provide a material retaining means.

Figure 9 shows a modified arrangement wherein the side walls 4 areomitted from the carrier belt 3 and wherein instead, side walls 44 areprovided on rigid grids 45 carried by the carrier belt. Side bars 43 arealso shown in respect of this arrangement.

Figure 10, shows a modification which is closely similar to thatillustrated in Figure 9 but wherein the carrier belt 3 is replaced bytwo laterally aligned flexible strips 4 46 one on each side of the valvemember 13 which is in direct engagement with the grid 45.

Referring to Figures 11 and 12, the endless filter medium conveyor 47comprises a series of rigid grids 48 carried by side chains 49 providedwith rollers 50. The valve member 13 engages the under surface of thegrids and a tube 38 connects each passage 14 of the member 13 with acomplementary passage 51 in each grid 48. Material retaining side bars43 carried by arms 52 fixed to frame 53 may be provided. The members 47and 13 are mounted for travelling movement on sprockets 54, which engagethe rollers 50. The rollers are supported on tracks 55 during theirhorizontal portions of travel. It will be observed that the side bars 43are located preferably at the feed end of the machine, except during awashing period, to retain the material on the filter medium while it isin freely fiowable condition.

The modification shown in Figure 13 is similar to that of Figure 12 withthe exception that each grid 48 is provided with end walls 56 to serveas filter medium guides.v

Figure 14 illustrates a modification wherein a plurality of metal plates57 constitute the supporting means carried by the side chains 49. Grids58 are fixed to the plates 57, such grids terminating inwardly of theside edges of the plates. Fixed to each edge of the grids is a fiexible(such as rubber) strip 59 which may have an upturned edge 60. Theflexible edge portions 59 are arranged for engagement by a tilting means41 to impart a troughlike shape to this portion of the filter assemblyduring its upper portion of travel.

The modification of Figure 15 is similar to that shown in Figure 14 butincludes a single flexible strip 61 mounted on the plates 57, grids 62being cast integral with or attached to the strip 61.

Figure 16 shows a modification wherein rigid grids 63, in which endwalls are omitted, are fixed to the plates 57.

Figure 17 illustrates a modification which is similar to that shown inFigure 16 but wherein the end walls 64 are provided.

Grease fittings 65 may be provided for internal lubrication of thechains 49, and to prevent the penetration of dust, grit or the like intothe moving parts of the chain.

An alternative resilient type of mounting for the vacuum box is shown inFigure 14, wherein adjustable springs 23 resiliently support the box forvsnug engagement with the valve member 13, and to relieve the weight onthe vacuum box top.

I claim:

l.,Vacuum filtering apparatus of the conveyor type comprising, a frame,a pair of horizontally disposed spaced apart drums mounted on saidframe, each of said drums having a similar circumferential groove ofsubstantially less width than said drum, an endless carrier belt mountedon said drums for rotational movement and having upper and lowerfiights, means for rotating said drums, a plurality of rigid rectilineargrids having a bottom wall and fixedly attached to the outer peripheralsurface of said carrier belt, each of said grids extending transverselyacross said carrier belts, an endless filtering medium carried insuperposed relation -on the upper fiight of said carrier belt, a vacuumbox xedly supported on said frame beneath said upper flight of saidcarrier belt, said vacuum box having the plane of its top wall spacedfrom said carrier belt and parallel therewith, said vacuum box having aslot in its top wall in longitudinal alignment with said circumferentialgrooves in said pair of spaced apart drums, an endless valve member,having a plurality of valve openings spaced along its longitudinalcenterline, mounted in said grooves of said drums and having a widthsubstantially equal to the width of said grooves, said valve memberbridging the space between said carrier belt and said vacuum box, eachof said grids having an opening in its bottom wall, all of said openingsin said bottom walls of said plurality of grids being in longitudinalalignment with the valve openings of said valve member, said carrierbelt having a plurality of openings therethrough registering with saidopenings in the bottom walls of said grids, and a rigid tube fixedlyattached in said opening in the bottom wall of said grid and extendingtherefrom through one of said openings in said carrier belt and intosaid valve opening in said valve member, whereby said opening in saidbottom wall of said grid, said opening in said carrier belt and saidvalve opening in said valve member are held in registry during rotationof said drums and said valve openings are held in alignment with saidslot of said vacuum box as said valve member slidingly traverses saidtop wall of said vacuum box.

2. Vacuum filtering apparatus of the conveyor type comprising a frame, apair of horizontally spaced apart lower trac members mounted on saidframe, a pair of similarly spaced upper track members in spacedsuperposed vertical alignment with said lower track members, sprocketsvertically mounted at each end of said upper and lower pairs of trackmembers, each of said sprockets mounted in vertical alignment with onemember of said pair of upper track members and one member of said pairof lower track members in bridging relation, each oi said sprocketshaving a plurality of spaced arcuate f grooves in its periphery, a pairof endless roller chains, each of said roller chains mounted to roll onone of said superposed upper and lower track members and enmesh withsaid sprockets at each end thereof, a plurality of plates having sideedges, each of said plates transversely a vacuum box xedly supported onsaid frame beneath said upper flight of said conveyor, said vacuum boxhaving the plane of its top Wall spaced from said carrier belt andparallel therewith, said vacuum box having a slot in its top wall inlongitudinal alignment with side openings Cil in said plates, an endlessvalve member, having a plurality of valve openings in spaced registrywith said openings in said plates, said valve member bridging the spacebetween said conveyor and said vacuum box, a rigid tube tixedly attachedin each of said openings in said plates and extending therefrom intosaid valve openings in said valve member, whereby said opening in saidplate is held in registry with said'opening in said valve member andsaid valve openings are heldin alignment with said slot of said vacuumbox as said valve member slidingly traverses said top of said vacuumbox, and an endless iilter medium carried by said upper flight of saidconveyor.

3. In a vacuum filtering apparatus of the conveyor type as claimed inclaim 2, a grid iixedly attached to said plate intermediate said filtermedium and said plate.

4. In a vacuum filtering apparatus of the conveyor type as claimed inclaim 2, a pair of material retaining side bars mounted on said frame,each of said side bars extending longitudinally of said upper ght ofsaid conveyor and adjacent one edge thereof, and` said side bars beingin substantial juxtaposition to said filter medium.

5. In vacuum filtering apparatus of the conveyor type as claimed inclaim l, said rigid grids terminating inwardly of the side edges of saidcarrier belt, a slide mounted on said frame adjacent said upper ight ofsaid carrier belt to engage the underside of said carrier belt extendingoutwardly of said grid and raise it out of the plane of said carrierbelt underlying said grid.

References Cited in the tile of this patent UNITED STATES PATENTS 18,369Butler Mar. l, 1932 2,034,784 Wallny Mar. 24, 1936 2,314,294 Wallny Mar.16, 1943 2,377,252 Lehrecke May 29, 1945 2,570,697 Nordengren Oct. 9,1951 2,688,406 Holland Sept. 7, 1954

